Dropped Colonies derive their name from their arrival. The ship arrives, the ship lands, the ship unloads the colony, the ship waits for a day at most, and the ship leaves. The people are left to their own devices.
Proper colonies require some planning, the bringing of supplies, and some careful selection of people.
Dropped Colonies don’t. Well, that is not completely true.
Someone had to look over some survey data and choose the best drop spots. So instead of hours and days of planning, someone checked a topographical map (which included resources) with a computer’s help for a few minutes.
Supplies do come with the people. But only a month or three’s worth of food, some camping equipment straight out of the 1800s, and a couple of tools for the community. There will be some seeds, and if the colony is lucky, some animals. Figure about 100kgs per person, of a standardized load. And the colonists are probably allowed 10Kgs for personal effects or equipment.
As for the selection of people. After a quick background check to avoid deserters, known psychopaths, those with genetic disorders, and so on, anyone who signs up is taken in.
Now a dropped colony is usually an all volunteer colony, but that is not always the case. Some people are given the choice to colonize or go to jail/ debtor’s prison/ and so on. Still if nobody checks on the colony for 100 years, nobody will know if they were just scooped up off the street and dumped there.
So it is a fairly random selection of people. They may or may not have any training or understanding of what a "rough and wild" lifestyle is like, or what living on the frontier is really like (despite what the videos show). They hopefully have a useful skill or understand farming. Volunteers usually have some clue about them, but many do not.
The most important thing for a colony to retain its technology is its ability to generate power. If they are lucky, they are sent with a generator or two. If it does not break, they can utilize some of the technology they brought with them (which isn’t much because the generators are known to break). Everything is lower tech because it is both cheaper and potentially replacable with resources on the planet. (We need to develop a copper mine so we can repair the generator’s brushes when they break).
So if these people manage to keep a lower tech world going, one with technology circa 1800s because they don’t have the power and the resources to do much more, they can survive quite nicely. Eventually they will develop some resources of their own and some offworld trade might develop. Then they are on their way to being "someplace".
However, for every someplace, there are several failed "no wheres".